True, this is because Darwin realised that organisms best suited to their environment are more likely to survive and reproduce, passing on their characters to their offsprings.
No. Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
Answer: Option (D) is the correct answer.
Explanation:
Non-metals are electron deficient in nature so, in order to complete their octet they need to gain electrons from metals or electron rich atoms.
Whereas metals are electron rich in nature so, in order to gain stability metals lose their valence electrons.
For example, atomic number of potassium is 19 and its electronic distribution is 2, 8, 8, 1. Whereas atomic number of chlorine is 17 and its electronic distribution is 2, 8, 7.
Therefore, sodium in order to gain stability will lose its valence electron to chlorine atom. Hence, an ionic bond will be formed resulting in the formation of KCl.
Thus, we can conclude that non-metals seek to gain electrons to have full outermost shells, while metals seek to lose electrons to have full outermost shells.
Answer: C.
Explanation: During a nuclear fusion reaction, it gets squeeze together so tightly that four hydrogen nuclei combine to form one helium atom. This is called nuclear fusion. In the process some of the mass of the hydrogen atoms is converted into energy in the form of light. The same process occurs in thermonuclear (fusion) bombs.
Answer:
c
Explanation:
to secrete hormones.this let the harmones travel to cells in other parts of body.
